FI98650B - Drill unit with hammering device - Google Patents

Abstract

Drill unit provided with a hydraulic or pneumatic hammer device 1 for drilling a hole or tunnel in the earth, in which unit the hammer device 1 is placed in the tip of the drill unit so as to produce hammer blows for one or more cutters 4, 6, 7 belonging to the cutter assembly, and the hammer device 1 contains a movable piston 2 which produces hammer blows. The centremost cutter 4 incorporates a joint face 12, which is known per se, for joining together ring cutters 6 of different sizes so as to increase the drill diameter in the cutter assembly, since at least the first ring cutter 6 which increases drill diameter can be withdrawn from the hole with the cutter 4, and at least the outermost 7 of the plurality of ring cutters which increase drill diameter can be left in the hole. <IMAGE>

Description

ουυυ DRILLING UNIT WITH IMPACTOR

The invention relates to a drilling unit as defined in the preamble of claim 1.

The prior art discloses drilling rigs in which the drilling stop can be changed by changing the blades. For example, Finnish patent application 931518 presents a typical example of this. The threaded spindle head comes out of the impactor. The piston of the percussion device strikes the end of the mandrel and the mandrel engages the percussion device in such a way that it is not usually replaced, but a blade of the desired diameter is screwed into the thread of the mandrel head. The end of the spindle stays inside the blade and does not come through the blade as a working part of the blade.

Finnish application 933074 discloses a central blade which is struck by the piston of an impact device and which central blade expands at the drilling end to a diameter as large as possible, but still to be withdrawn inside the protective tube.

The presented solutions describing the prior art will be expensive to manufacture if a similar structure is to be implemented [also in drilling larger holes, λ in a diameter of more than 400 mm.

• The solution is made expensive in the case of application 931518: the fact that a massive part with a channel drill and a blade stud must be made as a center drill for each diameter of the protective tube. per passenger.

Accordingly, the disadvantage of the publication 933074 is that each * diameter of the protective tube also has to make its own center; and this massive body also includes an extension of the body extending inside the impactor.

The object of the invention is to provide a new construction as a blade arrangement in which diameter transformations can be made with ring blade solutions considerably cheaper than the former blades around the central blade of the basic part. The present invention 2

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characteristic features are set out in the claims.

According to the invention, several hole diameters of different sizes are drilled, always using the same center blade in the blade arrangement, with which the central circle of all the holes is made. The diameter size is changed by adding enough ring blades around the center blade, the next ring blade always around the previous one so that the desired diameter size is reached. Attach at least one ring blade around the center blade, which is pulled out of the hole with the center blade. If the protective tube is left in the hole, the outermost ring blade of the blade assembly is also left in the hole. The outermost ring blade can be made very advantageously into a narrow ring. A set of ring blades of at least two blades in addition to the center blade shall be made so that each blade has a sufficient surface to receive impacts from the previous blade. In known solutions, the drilling spacing is increased by increasing the diameter of the outer ring blade without increasing its shock-absorbing surface, resulting in damage to the impact surface.

The center blade body is most preferably a nearly uniformly rotating body with a shoulder for transmitting impacts to the ring blade and a mounting for at least one ring blade. Thus, no further waste of material occurs in its preparation. It also includes · the necessary channel drilling for the rinse aid and drilling *. waste in such a way that the tire, or at least the outermost ·. the ring blade comes with only minimal channeling.

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In the following, the invention will be explained in more detail with reference to the accompanying drawing, in which • Figure 1 shows a blade arrangement according to the invention in section.

: Figure 2 shows the center blade from the front.

• ·.: In Fig. 1, the central blade 4 has an elongate body extending from the drilling surface inside the impact device 1 to the percussion piston 2. At the end of the body, there is a striking surface 13 on which the piston 2 strikes. As the rinse aid channels pass through the piston and the blade 4, there is a sealing sleeve 10 at the impact surface. The tip of the central blade 4 has an external thread so that "a ring blade 6 with the desired ul diameter can be wound around it. piston 2 strokes on blade 6.

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The outer diameter of the ring blade 6 extends to the protective tube 3 and the outer shoulder ring of the ring blade pulls the protective tube 3 during drilling. The protective tube has a corresponding drawbar.

In the blade arrangement according to the invention comprising at least two ring blades 6,7, the outer ring blade 7 is made into a narrow and low ring. This is made possible by the fact that the protective tube is pulled by the previous ring blade 6. The ring 7 can have some surfaces after the combustion cut without machining and its cross-sectional dimensions, e.g. 30 x 30 mm.

The drill diameter adjusting ring blades placed on top of each other are connected to each other and to the central blade 4, e.g. by means of a threaded connection or a bayonet connection, as the blade 7 is attached to the blade 6. Other connection methods can also be used, such as axial grooving between the blades to transmit rotational movement and blind locking to prevent the blade from slipping forward. The outermost ring blade 7 is most preferably with a bayonet connection so that it disengages in a rotational motion and can be left in the hole. The grooves 14 and the platforms 15 of the bayonet are shown in Fig. 1 on the surface of the ring blade 6.

• · • ·:: Figure 2 shows a central blade 4 with blade buttons' ·· 8 on the drilling surface and channels 9 leading to the drilling towards the center of the waste.

The joint diameter of the central blade 4 is Dp. Its preferred diameter ranges from 80 to 180% of the diameter of the percussion piston 2, but preferably from 100 to 130%.

On the other hand, the diameter Dp is 30 to 70% instead of the diameter of the hole to be drilled, whereby 70 to 30% of the hole diameter is covered by means of gears. With these solutions, the blade assembly becomes ··: easy to handle and variable in diameter. Ring ··: the blades are installed around the previous one in the required number so that the drilling diameter increases up to the protective tube 3. Then »♦ II the outer ring blade 7 is mounted, which in many cases is removed after drilling and left in the hole when the rest of the blade assembly is pulled out.

The connecting surface between the central blade 4 and the ring blade 6, as well as between the ring blades, be it a threaded, bayonet or other type of 98650 4 attachment, may include rinsing channels forwards or backwards, e.g.

With the solution according to the invention, only one central blade 4 is required for each very large diameter area, and the outermost ring blade left in the hole is always narrow and low in cross-section and less valuable to be sacrificed in the hole.

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Claims (6)

9865C A drilling unit equipped with a hydraulic or pneumatic percussion device (1) for drilling a hole or tunnel in the ground, wherein the percussion device (1) is positioned at the tip of the drilling unit to generate impacts on one or more blades (4, 7, 7) a movable impact piston (2) hitting the abutment surface (13) in the body of the central blade (4) of the blade assembly, characterized in that the central blade (4) has a connection surface (12) known per se for connecting ring blades (6) of different sizes by said surface to increase the drill diameter of the blade assembly, wherein at least the first drill-diameter-increasing ring blade (6) can be pulled out of the hole with the blade (4) and the second or second of the plurality of diameter-increasing ring blades pag e. Drilling unit according to Claim 1, characterized in that the blade (4) can be used as the middle blade of the blade assembly for drilling several holes of different sizes by placing one or more on it always in the previous ring blade (6). ) attached by a connecting surface (12) known per se. a ring blade (7) drilling the outer circumference of the hole. • · · • ·· »• · • · · · * * 11.’ Drilling unit according to Claims 1 and 2, characterized in that the body of the central blade (4) of the blade assembly comprises a rinse aid supply (li) and / or return channel (5) inside the body and / or or on the joint surface (12). • · »• · · • ·: *. Drilling rig according to one of the preceding claims 1 to 4. unit characterized in that the middle blade (4) • · * "comprises a shoulder or similar surface for transmitting impacts« · ·: V to the ring blade (6). ··· • · • · »» · Drilling unit according to one of the preceding claims 1 to 5, characterized in that the drilling diameter (Dp) of the central blade (4) 98650 is between 80 and 180% of the diameter of the percussion piston (2). Drilling unit according to one of the preceding claims 1 to 5, characterized in that the drilling diameter (Dp) of the central blade (4) is 30 to 70% of the diameter of the hole to be drilled.